This invention relates to electronic musical instruments, and more particularly to a method and apparatus for providing an intelligent accompaniment in electronic musical instruments.
There are many known ways of providing an accompaniment on an electronic musical instrument. U.S. Pat. No. 4,292,874 issued to Jones et al., discloses an automatic control apparatus for the playing of chords and sequences. The apparatus according to Jones et al. stores all of the rhythm accompaniment patterns which are available for use by the instrument and uses a selection algorithm for always selecting a corresponding chord at a fixed tonal distance to each respective note. Thus, the chord accompaniment is always following the melody or solo notes. An accompaniment that always follows the melody notes in chords of a fixed tonal distance creates a "canned" type of musical performance which is not as pleasurable to the listener as music which has a more varied accompaniment.
Another electronic musical instrument is known from U.S. Pat. No. 4,470,332 issued to Aoki. This known instrument generates a counter melody accompaniment from a predetermined pattern of counter melody chords. This instrument recognizes chords as they are played along with the melody notes and uses these recognised chords in the generation of its counter melody accompaniment. The counter melody approach used is more varied than the one known from Jones et al. mentioned above because the chords selected depend upon a preselected progression of either: up to a highest set root note then down to a lowest set root note etc., or up for a selected number of beats with the root note and its respective accompaniment chord and then down for a selected number of beats with the root note and its respective accompaniment chords. Although this is more varied than the performance of the musical instrument of Jones et al., the performance still has a "canned" sound to it.
Another electronic musical instrument is known from U.S. Pat. No. 4,519,286 issued to Hall et al. This known instrument generates a complex accompaniment according to one of a number of chosen styles including country piano, banjo, and accordion. The style is selected beforehand so the instrument knows which data table to take the accompaniment from. These style variations of the accompaniment exploit the use of delayed accompaniment chords in order to achieve the varied accompaniment. Although the style introduces variety, there is still a one-to-one correlation between the melody note played and the accompaniment chord played in the chosen style. Therefore, to some extent, there is still a "canned" quality to the performance since the accompaniment is still responding to the played keys is a set pattern.